This invention pertains to the structure and tracking of an array of parabolic-trough solar collectors. Parabolic-trough collectors can deliver higher temperatures than flat- plate systems. Parabolic-trough, single-axis tracking systems of 10 to 20 times concentration can operate at 212 to 350 degrees F. Flat-plate collectors operating at the same efficiency and insolation levels operate between 140 and 212 degrees F. The higher operating temperatures of the parabolic collectors make them much more efficient at solar cooling using desiccants, vapor compression, and sorption chillers. The higher temperatures are also easier to connect to conventional hot water heat, which usually use a boiler output water temperature of 180 degrees F.
The prior art contains a number of examples of methods for simultaneously rotating a parallel array of solar collectors. One common technique uses a pulley on one end of each collector. A continuous cable connecting all of the pulleys causes each of the collectors to rotate in unison. See, for example, U.S. Pat. No. 4,245,616, "Solar Tracking Device" of Wyland, issued Jan. 20, 1981. Somewhat different arrangements of this general concept are shown in U.S. Pat. No. 4,284,063, "Solar Power Generating System" of Watson, issued Aug. 18, 1981; and U.S. Pat. No. 4,114,594, "Device for Synchronously Rotating Solar Collectors" of Meyer, issued Sept. 19, 1978. However, none of these prior art references disclose or teach use of a large drive wheel supported by dolly wheels to not only overcome the tracking problems discussed in these references, but also to provide structural support for the collectors.